Issue 24459. Fix for 'Create Method' QF in different unit.

pkg/analysis_server/lib/src/services/correction/fix_internal.dart

Index: pkg/analysis_server/lib/src/services/correction/fix_internal.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index a2dd7297276500d91702245226b2e9823338aa34..ba774a99ffbf17a48cb12eedc0edd43435943896 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -1869,6 +1869,11 @@ class FixProcessor {
           sourcePrefix = eol;
         }
         sourceSuffix = eol;
+        // use different utils
+        CompilationUnitElement targetUnitElement =
+            getCompilationUnitElement(targetClassElement);
+        CompilationUnit targetUnit = getParsedUnit(targetUnitElement);
+        utils = new CorrectionUtils(targetUnit);
       }
       String targetFile = targetElement.source.fullName;
       // build method source